TrailCurrent Fireside

Central control display firmware for the TrailCurrent platform, running on the Waveshare ESP32-P4-WIFI6-Touch-LCD-7B 7-inch 1024×600 touchscreen dev board. Provides an on-device dashboard for monitoring and controlling devices on the TrailCurrent CAN bus via WiFi and MQTT.

Hardware Overview

• Board: Waveshare ESP32-P4-WIFI6-Touch-LCD-7B (7", 1024×600 IPS + GT911 capacitive touch)
• Microcontroller: ESP32-P4 (32 MB flash, PSRAM)
• WiFi: ESP32-C6 slave over 4-bit SDIO via ESP-Hosted
• Display: 7" 1024×600 MIPI-DSI (EK79007 controller)
• Touch: GT911 capacitive on I2C
• Audio: ES8311 codec (I2S DAC) + ES7210 ADC + class-D PA (PA enable on GPIO 53)
• Battery: on-board JST connector with charging IC + passive divider (200 kΩ / 100 kΩ) into GPIO 20 for voltage sense
• I/O: CAN, RS485, USB-OTG, USB-to-UART, MicroSD, 2× MIC, screw terminals
• Build System: ESP-IDF v5.3 or newer, target esp32p4
• Key Features:
  • Central dashboard for trailer system monitoring
  • Thermostat with temperature control
  • Configurable device control buttons
  • On-device setup wizard (WiFi + MQTT provisioning — no SD card required)
  • MQTT over TLS (mqtts://) for real-time data from the TrailCurrent platform
  • Light control with on/off and brightness via MQTT
  • GPS, energy, and air quality monitoring via MQTT subscriptions
  • Battery status via MQTT (from Solstice) and on-board battery telemetry via ADC divider
  • Alarm and TTS audio notifications
  • Color theme switching (light/dark)
  • Screen brightness and timeout controls
  • NVS-persisted user settings (theme, brightness, timeout, WiFi + MQTT credentials)
  • LVGL v8.4 UI designed with EEZ Studio

Firmware

This project uses ESP-IDF (not PlatformIO).

Prerequisites:

• ESP-IDF v5.3 or newer, targeting esp32p4.
• EEZ Studio — needed to export the UI to C. First-build users must run this before idf.py build.
• ESP32-C6 slave firmware flashed to the on-board C6 (per the Waveshare wiki setup instructions).

Setup:

# 1. Export the UI from EEZ Studio.
#    Open GUI/TrailCurrentFireside.eez-project
#    then File → Build (Ctrl+B). Output lands in main/ui/.

# 2. Build + flash + monitor.
idf.py set-target esp32p4
idf.py build
idf.py -p /dev/ttyUSB0 flash monitor

Firmware Dependencies

Resolved automatically by the ESP-IDF component manager. See main/idf_component.yml for the full list. Key ones:

• waveshare/esp32_p4_wifi6_touch_lcd_7b — first-party BSP for this board. Bundles the LCD panel driver (esp_lcd_ek79007), touch driver (esp_lcd_touch_gt911), LVGL port (esp_lvgl_port), and audio codec (esp_codec_dev with ES8311 + ES7210 support).
• lvgl/lvgl (~8.4.0) — pinned to match the .eez-project's lvglVersion.
• espressif/esp_hosted — ESP32-C6 slave communication over SDIO.
• espressif/esp_wifi_remote — WiFi via ESP-Hosted.
• espressif/mdns — mDNS discovery.

On-Device Setup Wizard

On first boot the device shows a setup wizard that walks the user through:

1. WiFi setup — scan-and-pick, WPA2 password entry with on-screen keyboard.
2. MQTT broker configuration — host, port, username, password.

Credentials are persisted to NVS, so a rebooted device auto-connects and jumps straight to the dashboard.

MQTT

The MQTT client connects over TLS (mqtts://) using credentials from NVS. It subscribes to:

• local/lights/+/status — Light on/off and brightness state
• local/energy/status — Energy monitoring data
• local/airquality/temphumid — Temperature and humidity
• local/airquality/status — CO2 (eCO2 ppm) and TVOC (ppb)
• local/gps/latlon, local/gps/alt, local/gps/details — GPS data
• local/battery/status — Battery state from Solstice

Light commands are published to local/lights/{id}/command.

Project Structure

├── DOCS/                                        # Documentation + vendor reference
│   ├── AUDIO_PHRASES.md                         #   TTS alarm phrase list + regeneration recipe
│   ├── PORT_NOTES.md                            #   Board bring-up notes (audio, battery, WiFi, etc.)
│   ├── ESP32-P4-WIFI6-Touch-LCD-7B.pdf          #   Waveshare board schematic
│   ├── ESP32-P4-WIFI6-Touch-LCD-7B-main/        #   Waveshare vendor examples (reference)
│   └── IMAGES/                                  #   Screenshots
├── GUI/                                         # EEZ Studio UI design files
│   ├── ASSETS/                                  #   Fonts (Roboto, FontAwesome) and images
│   └── TrailCurrentFireside.eez-project         #   Single source of truth for the GUI
├── ASSETS/                                      # Runtime backdrop / bar-graphic assets
├── components/                                  # Local components
│   ├── bsp_shim/                                #   Thin shim over the Waveshare BSP (`set_lcd_blight` → `bsp_display_brightness_set`)
│   ├── button_config/                           #   Configurable UI button metadata (icon, label, MQTT topic)
│   ├── fireside_config/                         #   NVS-backed device configuration
│   ├── mqtt_client/                             #   MQTT client with TLS + JSON dispatch
│   ├── peregrine_voice/                         #   Voice input pipeline (ES7210 ADC + wake-word)
│   └── wifi_setup/                              #   WiFi setup wizard + NVS-backed credentials
├── main/                                        # Application source
│   ├── main.c                                   #   Waveshare BSP bring-up + boot orchestration
│   ├── actions.c                                #   UI action callbacks (light control, settings, themes)
│   ├── vars.c                                   #   UI variable bindings + LVGL widget updates
│   ├── app_state.c                              #   App state machine + NVS wrappers
│   ├── alarms.c                                 #   Alarm handling + notifications
│   ├── audio.c                                  #   ES8311 codec playback via esp_codec_dev
│   ├── audio_assets.c                           #   Embedded PCM for TTS phrases (see DOCS/AUDIO_PHRASES.md)
│   ├── battery.c                                #   Local battery telemetry — ADC divider on GPIO 20
│   ├── perf.c                                   #   Perf probes
│   ├── sd_config.c                              #   MicroSD-based config import (optional)
│   ├── wifi_health.c                            #   C6 heartbeat / auto-restart
│   ├── mqtt_vars.h                              #   MQTT variable declarations
│   └── ui/                                      #   EEZ Studio generated UI code (do NOT edit)
├── CMakeLists.txt                               # Top-level CMake configuration
├── sdkconfig.defaults                           # ESP-IDF configuration defaults
├── sdkconfig.defaults.esp32p4                   # ESP32-P4 target-specific overrides
├── partitions.csv                               # Flash partition layout (8M factory app + 2M spiffs)
└── LICENSE                                      # MIT License

GUI Editing

The .eez-project is the single source of truth for every screen. Rules:

• Never hand-edit main/ui/* — EEZ Studio overwrites those on export.
• Never call lv_obj_set_pos, lv_obj_set_size, lv_obj_set_align, lv_obj_move_foreground, or any style-* geometry override on an objects.<widget> from C. Widget geometry lives in the JSON.
• Colors reference named tokens from the project palette; no hex literals in styles. If a new color is needed, add it via EEZ Studio's Colors panel first, then reference the name in the widget/style.

License

MIT License — See LICENSE file for details.

Contributing

Improvements and contributions are welcome! Please submit issues or pull requests.